ABS on an S12

[old-and-rusty]

Thanks Dan, but I`ve got a full PDF version of the s13 Service Manual. Plus I labelled all the loom as I disconnected it (as well as taking loads of notes) .

I`ve saved every single part from the s13 (including all fasteners and bolts...LOL...), so I know I have all the parts for the conversion already. I just need to make up a couple of new brake lines, which won`t be a problem, as I`ve got pipe flaring tools etc. Plus by using the complete s13 axle assembly, I can use the diff oil cooler that came off the car.

Sorry to hijack the thread Rich .

Regards,
Ian.

[JackieFan]

I was kinda offering the Manual for Richards benefit as he'll need to make a separate loom up

Will an S13 MC bolt to an S12 Servo and work? Is there a difference because of the ABS? Have you compared the two Ian?

[30psi]

I'm pretty certain it will bolt on. If a big Z32 one bolts to my Datsun then it's likely an S13 will bolt to S12

[JackieFan]

Sound's like its do-able. A machine shop could probably attach S13 rear wheel speed sensors to the S12 output shafts... somehow

[old-and-rusty]

Sorry Dan, didn`t realise you were offering Rich the info....LOL...

I haven`t compared the servos side by side, but I do know that s12`s used the G32 or M32 servos whereas the s13 used the M195T servos. As Martin says the MC`s are totally different - the s12 has a bigger cylinder bore and different outlets.

I will compare the two servos next time I`m in the garage and post up the results .

Regards.
Ian.

[30psi]

Use a Z32 one, it's the biggest master cylinder of them all. I wouldn't worry about using this over the S13 one unless you're using Z32 calipers.

The wheels sensors are nothing more than a hall sensor on a toothed wheel. so you could make up new toothed wheels on the back of the front hubs and also on the prop.

There is an issue that you need to check on however, and thats whether the different diff ratio will cause an issue with the ABS, because the rear will be turning at a slightly wrong speed compared to the front.

Unless you use an S13 back of course, but this has difficulties in itself.

[JackieFan]

The only reason I was thinking that the S13 MC would be best is because it'll match the ABS pump.

Not sure how the S13 is set up for ABS at the rear but if it only runs 1 sensor on the prop then you might be in luck. As far as I can work out the ABS controller only looks for unusual deceleration, so slight differences in wheel speed front to rear shouldn't effect it.

[old-and-rusty]

Dan,
The rear sensor can be found once the prop is removed. It`s just behind the flange that connects the prop to the diff (so just one bolt to remove the flange) .

I wonder if you could rig up the set up that a lot of kit cars use for the speedo sensor on the front hubs, do you think that would work Martin?

I know that TVR`s use this type of idea.

Regards,
Ian.

[sideways danny]

for the love of god why??? s13 ABS is positively dangerous, the worst ABS system known to man. Best mod you' can do to any s13 is remove the
ABS

[JackieFan]

What makes it so bad? Is it one of those systems that jumps in and doesn't let you have the pedal back until the car is wearing with either a tree, wall or innocent bystander?